Unlike other pump types, a gear pump does not need preparation beforehand and can operate dry at short episodes without causing damage to the pump. A gear pump should not be confused with a transfer pump, which is a device used in transferring liquids from one location to another.
How It Works
Known as the most common type of pump used in hydraulic fluid applications, a gear pump uses two meshed gears to pump liquids through displacement. For example, a gear oil pump is used for pumping oil, while other types may be used to pump not just oil but also water and other liquids. In general, these liquids lubricate the gears and are discharged as they flow in the distance between the gear’s teeth. These small spaces create a strong seal; therefore, the flow of the liquid to the gear’s intake is prevented.
There are three types of gear pump, and these include the following:
- External Gear Pump – This pump uses two similar gears which rotate in reversed directions. Here, the fluid is placed in the gap between the gear’s teeth and the pump’s side chamber. Power is then applied to the driving gear shaft, thus driving the other device. Usually, spur gears are used on external gear pumps. However, if there is excessive noise on the pump, herringbone or helical gears may become a better alternative.
- Internal Gear Pump – Also called as gerotor, an internal gear pump is typically sealed inside a case. On the external case, an external gear runs and makes a tight seal. On one side of the case, a small inner gear is placed to balance and mesh tightly with the external gear. On another side, distances can be seen between the internal and outer gears. And on the last side, a suction port which lets the fluid flow in and a pressure port which allows the fluid out are placed. To drive the whole mechanism, a motor is affixed to the internal gear.
- Hydraulic Gear Pump – Like internal gear pumps, this gear is placed on a sealed case and uses two meshed gears to pump hydraulic fluids to actuators and motors. These gears usually meet at the middle, though in some cases, they are connected in a different layout. At both ends of this pump, you will see an inlet and outlet valve which aid in the flow of fluid inside the case.
A gear pump is one of the most essential devices inside the motor; therefore, you should buy only from reputable gear pump manufacturers like Haight and Sulzer. Choose quality gear pumps in order to ensure your motor’s maximum performance and long life.